A multi hazard RISK assessment methodology accounting for cascading hazard events

The INFRARISK project is developing reliable stress tests on European Critical Infrastructure using integrated tools for decision-support. This aims to achieve higher infrastructure network resilience to rare and low probability extreme events. As part of the project, a hazard assessment methodology is developed to account for extreme natural hazards with cascading effects. Often hazard scenarios arising from cascading effects lead to disastrous consequences because such hazards are not prepared for. In particular, this paper focuses on the cascading hazard scenario involving earthquake triggered landslides. Traditional risk analysis considers each risk source as independent from the others. As a consequence, values for risk are usually defined regardless of interactions among the multiple risks present in a region. The current approach accounts for interaction between the two hazards in such a way that the probabilities of occurrence can be aggregated as part of an overall risk assessment methodology. The methodology is then demonstrated on a virtual road network case study as a proof of concept.